The attitude measuring systems have a wide variety of applications in many industrial fields. The measuring systems are a set of apparatuses for measuring spatial attitudes of an object (i.e. pitch angle, transverse roll angle, and course angle). In recent years, with the ever-decreasing cost of hardware, various types of attitude measuring systems have begun to enter the daily life of huge numbers of families. Taking mobile phones as an example, most smart phones currently on the market have built-in accelerometers, gyroscopes, and electronic compasses, which constitute a simple and low-cost attitude measuring system. However, currently, due to cost limitations, the built-in sensors of most attitude measuring systems have low accuracy and stability, thereby causing non-ideal measuring results of the entire attitude measuring system. Undoubtedly, calibrating the sensor without changing the hardware of the system is a very practical manner to improve the measurement accuracy of the whole system. Thus, studying the low-cost calibration method of attitude measuring systems is very worthwhile in practice.
The calibration and standardization of a sensor is always an important subject in the technical field of sensor technology. A large number of relevant researches have been carried out by domestic and foreign scholars with respect to the calibration solution of attitude measuring systems. A multi-position calibration method of MEMS inertial navigation using a rate turntable was studied by Wei Sun, Xinru Fu, et. al. An electronic compass calibration solution based on the Fourier transform under the condition of angle reference was studied by the scholars Binliang Ma, et al. An on-line calibration technology for the attitude measuring system based on the neural network and the UKF (Unscented Kalman Filtering) was studied by the scholars Wei Qin, et al.
Currently, studies are mainly focused on calibrating the attitude measuring system using calibration instruments such as turntable and the like. However, the specialized instruments for calibration are expensive and most of them are complicated to operate, thereby resulting in high production cost. On the other hand, in practice, the performance of the sensor in the system is continuously changing as the surrounding environment changes and the sensor itself ages. Thus, in practice, high precision is hard to achieve if merely relying on the calibration that was done on the sensor when the sensor left the factory. Additionally, in some current studies of calibration without instruments, either the calibration solution is too simple to be beneficial for the improvement of the actual measurement accuracy, or that the calibration solution is too complicated and requires the user to have high technical skills.